| Home | Organizers | Proceedings Editors | Proceedings Contributors | Search | | ||
|
|
|||
|
||||
|
|
||||
| Title: | OBSERVATION OF OCEAN WAVES BY LONG-RANGE OCEAN RADAR | |
| DOI No: | 10.1142/9789812701916_0088 | |
| Source: | COASTAL ENGINEERING 2004 (pp 1106-1118) | |
| Author(s): | SHOICHIRO KOJIMA
Okinawa Subtropical Environment Remote-Sensing, National Institute of Information, National Institute of Information and communication Technology, 4484, Aza-Onna, Onna, Kunigami, Okinawa, 904-0411, Japan KENJI SATOH Okinawa Subtropical Environment Remote-Sensing, National Institute of Information, National Institute of Information and communication Technology, 4484, Aza-Onna, Onna, Kunigami, Okinawa, 904-0411, Japan TAKESHI MATSUOKA Okinawa Subtropical Environment Remote-Sensing, National Institute of Information, National Institute of Information and communication Technology, 4484, Aza-Onna, Onna, Kunigami, Okinawa, 904-0411, Japan |
|
| Abstract: | National Institute of Information and Communication Technology (NiCT) is developing the Long-Range Ocean Radar (LROR) for measuring the surface currents and waves in the coast and ocean. LROR can simultaneously measure the waves in all observation area by using the digital beam forming (DBF) technique, and also can measure wider observation area than other ocean radars because the wave length of the electric wave used by LROR is longer than that used by other ocean radars. This study clarifies the accuracy and validity of the directional wave spectrum observed by the LROR. Therefore, the precision of the receiving signal of the LROR is evaluated by the directional spectrum measured by the buoy. As a result, it was clarified that the noise level is changed depending on the LROR site location and the ionosphere condition. In particular, the noise level is greatly changed by the ionosphere condition. At nighttime, the noise level is large because the D layer in the ionosphere is disappeared, so it is difficult to measure the directional wave spectrum by the LROR. At daytime, however, it is clarified that the directional wave spectrum can be estimated from the receiving signals measured by the LROR when the noise level is low. Finally, we estimate the directional wave spectrum from the receiving signals at daytime, and compared with the directional wave spectrum measured by the buoy. As a result, it is clarified to estimate the directional wave spectrum by the LROR at daytime. | |
| Full Text: | View full text in PDF format (536KB) | |
| TOC: | Back to Table of Contents | |
|
||